1. Field of the Invention
The present invention relates generally to a fluid mixing and/or an aerating apparatus. The invention also relates to a venturi-type or suction-type fluid mixing and/or aerating device, and also to a device for causing a first fluid to dissolve a second fluid therein to its saturation state or substantially to its saturation state.
2. Description of the Related Art
A variety of fluid mixing devices have been devised wherein a venturi is adapted with different types of mechanical injectors. Fluid flow through pipes and other flow devices have associated losses inherent to the device, depending on the type of material the flow channel or device is composed of, and the manufacturing method used to produce the fluid flow device. Also, depending on the physical features of the channels (i.e. surface texture, roughness, etc.) or the surfaces on which a fluid traverses, pressure head losses in the flow results.
These losses within a flow device such as a venturi driven flow system vary from device to device, depending on the mechanical element adapted thereto. For example, losses associated with mechanical elements such as check valves, mechanical injectors, blowers, compressors, pumps, etc. during the injection of liquid, air or other elements within the primary flow of fluids through the flow device serve to minimize fluid flow and increase the pressure differential.
Generally, the principal goal for maintaining fluid flow within a network of interconnected flow channels or elements, according to first principles in mechanics of fluids, is to minimize total pressure head losses associated with the respective mechanical elements. Most of the conventional fluid flow devices have failed to reduce the total head losses as herein described by the instant invention. Without significantly reducing the pressure head losses associated with the mechanical elements as recited above, a significant drop in the volume flow rate occurs within most flow devices. This directly affects the mixing of multiple fluids within the primary fluid channel or stream of typical fluid flow devices.
For example, U.S. Pat. No. 2,361,150 issued Petroe discloses a method and apparatus for admitting chlorine to a stream of pulp stock via a plurality of injectors or nozzles during the effluent stage. The mechanical injectors are peripherally disposed within the flow stream or path having a direct contribution to the total head loss unlike the differential injector as herein described.
U.S. Pat. No. 2,424,654 issued to-Gamble discloses a fluid mixing device which also suffers from head losses as recited above. A venturi flow device having an adjustable throat section includes baffles disposed directly in the flow path or throat (i.e. in-line injectors) of the device which contributes to the total head loss as similarly taught by the patent of Gamble. Other varieties of in-line injectors are those taught by King (U.S. Pat. No. 3,257,180), Van Horn (U.S. Pat. No. 3,507,626), Baranowski, Jr. (U.S. Pat. No. 3,768,962) and Longley et al. (U.S. Pat. No. 4,333,833).
U.S. Patents issued to Secor (U.S. Pat. No. 398,456), and Mazzei (U.S. Pat. No. 4,123,800) disclose a venturi flow device comprising a mixer injector disposed at the throat section of the device. The patent of Mazzei in particular comprises a plurality of port means which are angularly spaced-apart around the throat section and interconnect an annular chamber disposed within an inside wall of the throat portion. This particular design is similar to that of the instant invention in that, it attempts to minimize a pressure drop within the channel. The injector of Mazzei, however, fails to reduce losses at the throat section unlike that of the instant invention as herein described.
U.S. Pat. No. 5,693,226 issued to Kool discloses an apparatus for demonstrating a residential point of use water treatment system wherein an injection port or suction branch injects a contaminate material in a direction perpendicular to the flow stream via hoses adapted thereto. The differential injector according to the instant invention is different in that the injections are made in a direction parallel to the flow stream which significantly reduces head losses attributed to the different al injector as herein described.
U.S. and Foreign Patents by Monroe (U.S. Pat. No. 4,765,373), Luft et al. (AU 203339), Gretton-Lowe (GB 802,691), Hollins (GB 870,525) and Evans (GB 132074) disclose flow devices generally relevant to that of the instant invention.
The difference between the instant invention and the related art is that the differential injector according to the instant invention provides mixing and/or aeration without the additional need of mechanical injectors which increase the pressure head losses in the primary flow stream. Mixing or aeration occurs by injection in the general flow direction of a main flow stream with very low losses compared to conventional flow devices.
In this regard, none of the above inventions and patents, taken either singularly or in combination, is seen to describe the instant invention as claimed. Thus a differential injector solving the aforementioned problems is desired.
The injector according to-the instant invention is a fluid mixing and/or aerating device having a primary fluid inlet. Some embodiments also include a constricting primary fluid inlet and an elongated throat section to increase the velocity of the primary fluid flow. A secondary fluid is pulled into the forward portion of a discharge outlet, through at least one channel which is recessed in the wall of the device, by suction action produced by the primary fluid as it passes out of the inlet section to an enlarged-size, pressure releasing, discharge section. One or a plurality of ports feeds the secondary fluid into the at least one recessed channel. The secondary fluid ports are connected to a secondary fluid injection port or are open to the atmosphere.
After the discharge section, the mixed fluids can be passed through an elongated conduit section to cause the secondary fluid to become more dissolved in the primary fluid, up to its saturation state.
Accordingly, it is a principal object of the invention to provide a differential injector for reducing total head loss in a flow device by injection.
It is another object of the invention to provide a is differential injector which mixes fluids and/or aerates fluids with a minimum number of attached mechanical elements.
It is yet another object of the invention to provide apparatus for mixing primary and secondary fluids such that the secondary fluid is dissolved in the primary fluid up to its saturation state.
It is a further object of the invention to provide a differential injector which is easily assembled and disassembled for inspection, cleaning or repair.
It is still another object of the invention to provide improved elements and arrangements thereof for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.